# Electronics

**Academic Year 2023/2024**- Teacher:

**EGIDIO RAGONESE**

## Expected Learning Outcomes

**Knowledge and understanding**

The course aims to provide basic knowledge on the modeling of electronic devices, on the operation of analog and digital circuits in CMOS technology and on the most common circuit configurations that make use of operational amplifiers. The course also provides knowledge on the use of CAD software (i.e., LTSPICE) for circuit simulation.

**Applying knowledge and understanding**

At the end of the course, student will have an overview of electronic devices and applications in which they are used. He will be able to analyze and design simple analog and digital circuits, also by CAD tools.

**Making judgements**

Students will be able to design simple analog and digital circuits by making proper and autonomous design choices. Proper numerical exercises and computer simulations will refine the making judgement skill.

**Communication skills**

Students will acquire the technical language of circuit electronics. They will also be able to communicate the proper design choices made to solve a circuit problem. Oral exam allows students to refine technical language and communication skills.

**Learning skills**

Students can expand their knowledge of electronics through the study of the recommended textbooks and through the ideas offered by the seminar activities organized within the course.

## Course Structure

The course includes lectures and numerical, simulation (CAD) and experimental exercises. The latter are aimed at putting into practice and consolidating the theoretical contents as well as the analysis and the design techniques developed. Seminars will be organized by researchers and designers from companies operating in the microelectronics sector.

Should teaching be carried out in mixed mode or remotely, it may be necessary to introduce changes with respect to previous statements, in line with the programme planned and outlined in the syllabus.

Learning assesment may also be carried out on-line, should the conditions require it.

## Required Prerequisites

The course requires the student

- is able to carry out the study of a mathematical function (Mathematical Analysis I)
- know the tools of calculus (Mathematical Analysis I)
- know and know how to manipulate the physical quantities related to electromagnetic phenomena (Physics II)
- know the fundamentals of circuit theory including its main theorems (Electrotechnics)
- know and have skills in solving linear time-invariant electrical circuits in steady state, sinusoidal and transient regime also through the use of the Laplace transform (Electrotechnics)

## Attendance of Lessons

## Detailed Course Content

**Introduction to Electronics:**A brief history of electronics. Classification of Electronic Signals. A/D and D/A Converters. Notational Conventions. Dependent sourced. Important Concepts from Circuit Theory (Kirchhoff’s lows, dividers, Thevenin and Norton Equivalents). Frequency Spectrum of Electronic Signals. Amplifiers.**Solid-State Electronics**. Solid-State Electronic Materials. Covalent Bond Model. Intrinsic carrier concentration. Mass action. Drift Currents and Mobility in Semiconductors. Velocity Saturation. Resistivity of Intrinsic Silicon. Impurities in Semiconductors. Electron and Hole Concentrations in Doped Semiconductors. Diffusion Currents. Total Current. Energy Band Model.**Solid-state Diodes and Diode circuits:**Junction diode. The I/V Characteristics of the Diode. Diode Characteristics Under Reverse, Zero, and Forward Bias. Diode Temperature Coefficient. Reverse Breakdown and Zener Diode. pn Junction Capacitance in Reverse Bias and Forward Bias. Dynamic Switching Behavior of the Diode. Large signal Model. Diode SPICE Model. Diode Circuit Analysis. Load-Line Analysis. Analysis Using the Mathematical Model for the Diode (small signal resistance). Constant Voltage Drop Model. Multiple-Diode Circuits. Half-Wave Rectifier Circuits with R, C and RC load. Full-Wave Rectifier and Bridge Circuits. Voltage regulator with Zener diode. Photo Diodes and Photodetectors. Schottky Barrier Diodes. Solar Cells. Light-Emitting Diodes**MOS Transistors:**Characteristics of the MOS Capacitor. Accumulation Region. Depletion Region. Inversion Region. The NMOS Transistor. Qualitative I/V Behavior of the NMOS Transistor. Triode Region Characteristics of the NMOS Transistor. On Resistance. Saturation of the I/V Characteristics. Mathematical Model in the Saturation (Pinch-Off) Region Transconductance. Channel-Length Modulation. Body Effect. PMOS Transistors. MOSFET Circuit Symbols. NMOS Transistor Capacitances in the Triode Region. Capacitances in the Saturation Region. Capacitances in Cutoff. MOSFET biasing (4 resistors network) and analysis. Modeling in SPICE.**Digital circuits**: Ideal Logic Gates. Logic Level Definitions and Noise Margins. Logic Gate Design Goals. Dynamic Response of Logic Gates. Rise Time and Fall Time. Propagation Delay. Power-Delay Product. Review of Boolean Algebra. CMOS logic circuits. Static characteristics of the CMOS Inverter. CMOS Voltage Transfer Characteristics. CMOS NOR and NAND Gates. Design of Complex Gates in CMOS. Cascade Buffers and Delay Model. Optimum Number of Stages. Bistable latch. SR Flip-Flop. JK Flip flop. Flip-Flop race condition. The D-Latch Using Transmission Gates. Master-Slave Flip-Flop. Edge triggered Flip flop. Counters and registers. Random Access Memories (RAMs). 6-T cell. Dynamic RAMs. 1-T cell.**Operational Amplifiers:**An Example of an Analog Electronic System. Amplification. Voltage Gain, Current Gain and Power Gain. The Decibel Scale. The Differential Amplifier. Differential Amplifier Voltage Transfer Characteristic. Differential Voltage Gain. Differential Amplifier Model. Ideal Operational Amplifier. Assumptions for Ideal Operational Amplifier. The Inverting Amplifier. The Transresistance Amplifier. The Noninverting Amplifier. The Unity-Gain Buffer, or Voltage Follower. The Summing Amplifier. The Difference Amplifier. The Integrator. The Differentiator. Nonidealities: Common mode gain. CMRR. I/O resistances. Offset. Slew rate.**Small-signal Modeling and linear amplification:**The Transistor as an Amplifier. Coupling and Bypass Capacitors. Circuit Analysis Using dc and ac Equivalent Circuits. Small-Signal Modeling of the Diode. Small-Signal Models for Field-Effect Transistors. Intrinsic Voltage Gain of the MOSFET. The Common-Source Amplifier (Voltage Gain. I/O resistances). Power dissipation and signal swing. Amplifiers classification. CS, CD, CG configurations. CS with resistive degeneration. AC-coupled multi stage amplifiers.**Frequency response:**Frequency response of Amplifiers, Midband gain, Low and high cutoff frequencies (fL and fH). Estimation of f_{L}through the short-circuit time constant method for CS, CG, CD amplifier. High-frequency MOSFET model. Transition frequency, f_{T}. Channel Length Dependence of f_{T}. Analisi ad alta frequenza dell’amplificatore source comune. L’effetto Miller. High-Frequency C-S Amplifier Analysis. The Miller Effect. Common-Emitter and Common-Source Amplifier High-Frequency Response. Estimation of f_{H}through the open-circuit time constant method for CS.**Computer****simulations of electronic circuits:**LTSPICE.

## Textbook Information

1. Jaeger-Blalock, Microelettronica Ed. Mc-Graw-Hill V Edizione.

2. Sedra-Smith, Circuiti per la Microelettronica, Edises.

## Course Planning

Subjects | Text References | |
---|---|---|

1 | Introduction to electronics | 1, chapter 1 |

2 | Introduction to the LTSpice simulator. Description of the netlist and solving simple linear circuits. | Slides and on-line manuals |

3 | Solid state electronics | 1, chapter 2 |

4 | Solid state diodes and circuits with diodes | 1, chapter 3 |

5 | Exercise: simulation of diode circuits | Slides |

6 | The MOS transistor | 1, chapter 4 |

7 | Exercise: circuit simulation of MOS transistors | Slides |

8 | Introduction to digital electronics | 1, chapter 6 |

9 | Complementary MOS logic circuits complementari | 1, chapter 7 |

10 | MOS memories and sequential circuits | 1, chapter 8 |

11 | Exercise: simulation of logic gates, flip-flops and counters | Slides |

12 | Operational amplifiers | 1, chapter 10 2, chapter 2 |

13 | Applications of operational amplifiers | 1, chapter 10 2, chapter 2 |

14 | Exercise: circuit simulation with operational amplifiers | Slides and on-line manuals |

15 | Small signal models and linear amplification | 1, chapter 13 |

16 | Single transistor and multistage AC-coupled amplifiers | 1, chapter 14 |

17 | Exercise: simulation and design of single transistor amplifiers | Slides |

18 | Frequency response | 1, chapter 17 |

19 | Exercise: simulation of the frequency response of a CS amplifier | Slides |

## Learning Assessment

### Learning Assessment Procedures

Learning is verified through an oral interview. The oral interview generally takes place with three questions focused on as many topics of the course (typically, a question on electronic devices, one on analog circuits and one on digital circuits), on which the student must demonstrate adequate understanding, mastery of the topics discussed. and clarity of presentation. During the oral interview, students may be asked to set up a numerical exercise concerning the analysis or design of an electronic circuit. The average duration of the oral interview is 40 minutes. The final grade will take into account the student's participation in lessons (through the presence and assigned exercises) and, with greater weight, the outcome of the oral interview.

Verification of learning can also be carried out on-line, should the conditions require it.

### Examples of frequently asked questions and / or exercises

Below are listed, by way of example and in a non-exhaustive manner, some topics that are asked during the oral interview.

Equation of the current in the diode

Small-signal model of the PMOS transistor

Half-wave and full-wave rectifier circuits

Voltage regulator.

Virtual short circuit

Applications of operational amplifiers

Transisition frequency of the MOS transistor

Frequency response of a CS

CMOS logic gates

Latch and ﬂip- ﬂop

**VERSIONE IN ITALIANO**